Key parameters at a glance

A radius of 1.11 Earth radii
A mass of 1.83 Earth masses
Surface gravity around 1.49 g
An orbital period of 0.301 days
Semi-major axis 0.0056 AU
Equilibrium temperature 1,122 K (849 °C)
Distance from Earth 88.94 light-years
Earth Similarity Index 0.265
Travel time at Voyager 1 speed 1,568,413 years
Almost certainly tidally locked to its host star given the close orbit

TOI-4552 b Planet Profile

Physical Specs

Radius

1.11 R⊕

Radius (Jupiter)

0.099 R♃

Mass

1.83 M⊕

Mass (Jupiter)

0.006 M♃

Density

7.74 g/cm³

Surface Gravity

1.49 g (Earth)

Classification

Planet Type

Rocky Terrestrial

ESI Score 0.265

HZ Position Inner

Controversial No

Discovery

Year 2026

Method Transit

Facility Transiting Exoplanet Survey Satellite (TESS)

Telescope 0.1 m TESS Telescope

Size rank in cohort

Rank by radius

#209of 570

top 36.5%

This planet

1.11R⊕

Rocky Terrestrial median

1.01R⊕

Nearest-size peers

Kepler-124 d 1.11 R⊕ Kepler-327 b 1.11 R⊕ Kepler-333 c 1.11 R⊕

Metric	Earth	TOI-4552 b	Jupiter
Radius (R⊕)	1.00	1.11	11.21
Mass (M⊕)	1.00	1.83	317.83
Density (g/cm³)	5.51	7.74	1.33
Surface Gravity (g)	1.00	1.49	2.53
Insolation (S⊕)	1.00	263.00	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	1.830 M⊕	Direct mass measurement (not derived).

Star Catalogue Identifiers

TIC

TIC 248250955

Gaia DR2

Gaia DR2 5948579462188230144

Gaia DR3

Gaia DR3 5948579462188230144

System

TOI-4552

Percentile among Rocky Terrestrial cohort

Radius 1.110 R⊕ · percentile 61 / cohort 570

Mass 1.830 M⊕ · percentile 76 / cohort 570

Orbital period 0.30 d · percentile 1 / cohort 567

Distance 27.27 pc · percentile 12 / cohort 566

ESI 0.265 · percentile 28 / cohort 570

Orbit & Habitability

Orbital Dynamics

Period

0.301 days

Semi-major axis

0.0056 AU

Eccentricity

0.000

Inclination

87.77 °

Year Length

A year here lasts roughly 7.2 hours long on a nearly circular orbit at a mean orbital distance of 0.0056 AU.

Transit Fingerprint

Depth

0.126 %

Duration

0.640 h

Impact parameter b

0.160

Rp / R★

0.035200

Transit midpoint (BJD)

2,459,361.8859

Photometric dip

Transit produces a flux drop of 1,258 ppm lasting ≈ 0.64 h.

Extended Orbital Architecture

Planet / star radius ratio

0.035200

Impact parameter (b)

0.160

RV semi-amplitude (K)

4.320 m/s

Transit mid-time (BJD)

2,459,361.8859

Long. of periastron (ω)

90.00°

Angular separation (arcsec)

0.20600

Eq. Temperature

1,122K

(849 °C)

Insolation (S⊕)

263.00

Earth = 1.00

Earth Similarity (ESI)

0.265

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched. Close-orbiting tidally-locked around a cool host.

Detection Signatures

Transit photometry

A transit dip has been observed from at least one telescope.

Radial velocity

Stellar wobble has been measured spectroscopically.

Discovery Paper

Primary reference

Srivastava et al. 2026

Instrument

TESS CCD Array

Publication

2026-03

Observation locale

Space

Discovery cohort

Planets confirmed in 2026 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).

TOI-2094 b · Super-Earth TOI-6716 b · Rocky Terrestrial TOI-1080 b · Rocky Terrestrial TOI-1243 b · Sub-Neptune TOI-4529 b · Super-Earth TOI-7384 b · Sub-Neptune LHS 1903 d · Sub-Neptune LHS 1903 c · Sub-Neptune TOI-5734 b · Sub-Neptune TOI-5788 c · Sub-Neptune LHS 1903 b · Super-Earth TOI-5788 b · Super-Earth

Host System: TOI-4552

Spectral Class

M-type red dwarf

Effective Temperature

3,258 K — cooler than the Sun (5,778 K)

Estimated Age

—

Stellar Radius

0.287 R☉

Stellar Mass

0.262 M☉

Metallicity [Fe/H]

-0.07

Extended Stellar Properties

Surface gravity (log g)

4.940 dex

Stellar density

15.803 g/cm³

Systemic radial velocity

-26.22 km/s

Metallicity ratio

[Fe/H]

Distance

27.27 parsec

Light-years 88.94 ly

V-band magnitude

14.44 mag

Voyager-speed travel 1,568,413 yr

Multi-band Host Photometry — 6 bands

Astrometric Data

Parallax

36.644 mas

Total Proper Motion

491.319 mas/yr

PM Right Ascension

-134.73 mas/yr

PM Declination

-472.49 mas/yr

Galactic Cartesian (pc)

x = -0.062 · y = -0.671 · z = -0.739

Equatorial (J2000)

RA 264.71426° · Dec -47.63705°

Galactic ℓ, b

343.297° · -8.636°

Ecliptic λ, β

266.092° · -24.269°

HTM-20 index

1634169204